JPH077175B2 - Shutter device capable of correcting running characteristics - Google Patents

Description

TECHNICAL FIELD OF THE INVENTION The present invention relates to a slit exposure type shutter device for a camera.

(Background of the Invention) Recently, technology for reducing the weight of blades of slit exposure type shutters has advanced, and the operating speed of the blades has been extremely increased, and the total operating time, that is, the total exposure time has been shortened.

Therefore, in the case of an electronic flash device (hereinafter, abbreviated as speedlight) having a slightly long light emission time, it has become possible to complete the traveling operation of the shutter, that is, the exposure operation within the light emission time. Hereinafter, this method is referred to as slit synchronization photography.

If this slit synchronized shooting becomes possible, it will be possible to shoot at a high shutter speed, which was previously impossible with speedlight shooting.Furthermore, by utilizing the slow shutter speed from the past, emission is completed while the shutter blades are fully open. When combined with the so-called open flash method, the speedlight can be used with an extremely wide shutter speed, and therefore, the range of use of speedlight photography becomes wide, which is convenient for photography.

However, performing slit sync photography with a conventional shutter device has the following drawbacks. Figure 10 and
This will be described with reference to FIG. 10 (A) and 11 (A)
Shows the light emission characteristics of the speedlight, and shows that the emitted light energy is large at the initial stage and is small at the final stage. 10 (B) and 11 (B)
Shows the running characteristics when the leading shutter blade 1C and the trailing shutter blade 2C form a slit and run from the starting edge A to the trailing edge B of the film screen, and FIGS.
It shows that they correspond to the light emission characteristic chart of FIG. FIGS. 10 (C) and 11 (C) show the exposure amount when the screen is exposed by the shutter with the light emission characteristics, and the horizontal axis shows the exposure amount, and FIGS. This corresponds to the diagram of FIG. 11 (B).

FIG. 10 shows a case where slit exposure is performed at a high shutter speed, and FIG. 11 shows a case where slit exposure is performed at a shutter speed lower than the shutter speed. This low shutter speed means the shutter speed on the low speed side in the high shutter speed, and it goes without saying that it is higher than the shutter speed at which slit sync photography is possible. For example, if the high shutter speed is 1/4000 or higher, The shutter speed is about 1/1000.

In Fig. 10, the slit exposure is performed at the high shutter speed while the speedlight is emitting light. At this time, since the shutter speed is high, the total exposure time is short. As shown in FIG. 6C, the exposure amount at the position slightly closer to the starting end A in the central portion of the screen may increase, but since the starting end A and the ending end B have almost the same exposure amount, there is sufficient practicality. . Therefore, in such exposure at a high shutter speed, the slit synchronization photography does not significantly affect the exposure unevenness in the screen.
However, when a high-speed shutter is used, the effective guide number of the speedlight is much smaller than the guide number originally used by the speedlight used, and the shooting range is limited. In addition, speedlight photography is often performed at a synchronized shutter speed or higher without taking such a high shutter speed. However, in this case, there is a drawback that the exposure unevenness is severe as described below.

As shown in FIG. 11, when the shutter speed is slightly slower than that in FIG. 10, for example, at the low shutter speed (about 1/1000), the total exposure time is long, so Since the exposure is still being performed, the portion of the screen end B is relatively underexposed as seen in FIG. 11 (C). In this way, the difference in exposure amount between the start edge A and the end edge B of the screen becomes large, which causes uneven exposure. Therefore, it can be seen that the slit exposure with the low shutter speed has larger exposure unevenness than the slit exposure with the high shutter speed. But,
Even if the slit synchronized photographing is performed, the photographing at the low shutter speed is very useful, and therefore, as described above, the slit exposure having large exposure unevenness causes many inconvenient photographing.

(Object of the Invention) The present invention provides a shutter device that allows a photographer to intentionally control the exposure unevenness of the screen according to the photographing situation, and can perform photographing that suits the photographing intention, especially when performing slit synchronized photographing. It is an object of the present invention to provide a shutter device that reduces exposure unevenness on the screen and enables speedlight photography over a wide range of shutter speeds.

(Summary of the Invention) In order to achieve such an object, the present invention is provided with a traveling speed varying means for varying an average traveling speed of one or both of a shutter opening member and a shutter closing member, and the traveling speed varying means according to photographing conditions. It is a technical point that the above function is intentionally controlled so that the uneven exposure of the film screen can be controlled.

(Embodiment) FIG. 1 is a conceptual diagram of a first embodiment of the present invention. FIG. 1 (A) shows a light emission characteristic of a speedlight, and FIG. 1 (B) shows a shutter front blade 1 (trajectory). 1C) and the shutter rear blade 2 (trajectory 2C) form a slit and show the traveling characteristics when traveling from the start edge A to the end edge B of the screen, and correspond to the emission characteristic diagram of FIG. 1 (A). ing. FIG. 1 (C) shows the exposure amount when the screen is exposed by the shutter with the light emission characteristics, the horizontal axis shows the exposure amount, and the vertical axis shows the screen width.

Referring to FIG. 1B, the operation of the shutter will be described when the shutter is moved within the light emission time of the speedlight to perform the slit sync photography for completing the exposure. 11th
When performing slit sync photography at the low shutter speed shown in the figure, the locus 2C 'or 2C "is drawn by lowering the average traveling speed of the shutter rear blade 2 as compared with the shutter front blade 1 as seen in FIG. 1 (B). To change the exposure unevenness.

First, in the example in which the trailing blade 2 of the shutter draws the locus 2C ′, the exposure amount at the leading edge A in slit synchronization photography is
The average traveling speed of the rear shutter blades 2 is reduced so that the absolute values of the deviations between the maximum exposure amount and the minimum exposure amount in the screen are almost equal. However, the average traveling speed refers to the distance from the starting end A to the ending end B divided by the time required for the shutter blades to travel. In this method, the uniformity of the exposure amount of the screen with respect to the light emission of the speedlight is insufficient as indicated by the one-dot chain line b ₁ ′ in FIG. 1 (C), but the set shutter speed (the shutter speed in the case of locus 2C is set. ) Is small, the ratio of overexposure at the end B is relatively small even when shooting with lighting other than the speedlight, for example, natural light (sunlight). In the case where the subject is conservatively exposed to the speedlight, it is convenient because it is possible to shoot with less uneven exposure even on the background of the subject.

Further, in the example in which the trailing blade 2 of the shutter draws the locus 2C ″, the exposure amount in the screen given by the speedlight light at the time of the slit synchro photography is made substantially equal at the start end A and the end B as shown in FIG. 1 (C). The average traveling speed of the shutter rear blade 2 is further reduced from the locus 2C '. In this method, the uniformity of the exposure amount of the screen with respect to natural light is insufficient because the traveling is corrected, but FIG. C) Dashed line shown
Since the uniformity of the exposure amount of the screen with respect to the emission of the speedlight such as b ₁ ″ is sufficient, it is possible to shoot with less exposure unevenness in slit synchronization shooting in a place with little natural light. The exposure unevenness can be controlled by changing and correcting the value, and shooting can be performed according to the shooting intention.

At this time, as shown in FIG. 1 (C), the shutter rear blade 2
Although there is a sufficient effect of correcting unevenness in exposure without correcting the running start time of the
Properly set to a time earlier than time t ₂ as t ₂₁
As shown in the figure, run the blades behind the shutter to change the exposure amount
If b _{1 is set} , it is more effective for shooting. That is, in the slit sync photography, the shutter rear blade 2
As described above, the running characteristic is the locus 2C 'and the exposure amount is the one-dot chain line.
The total exposure amount and shutter speed of the screen when changed as shown in b ₁ ′ are the total exposure amount (solid line b) and shutter speed (trajectory) of the screen when the running characteristics of the rear shutter blades 2 are not corrected.
2C), so the shutter speed (trajectory 2C) and exposure amount (two-dot chain line) should be almost equal.
If b ₁ ) is configured, the effect of preventing the blur of the background of the subject is maintained, and it is also convenient in the exposure calculation that determines the shooting conditions. That is, the exposure amount does not change much as compared with that before the correction of the running characteristics, and the light amount that can be effectively used by the speedlight during slit synchronization shooting is substantially equal to the expected light amount, so that a preferable shooting result is obtained. It should be noted that the running characteristics of the shutter rear blade 2 are changed to the locus 2C '
However, an example of advancing the timing of starting the trailing blade when the locus is set to 2C ″ is not shown, but the timing of launching the trailing blade may be set according to the same concept as described above.

Next, a second embodiment of the present invention will be described in which a correction method different from the correction method of the traveling characteristics of the shutter device shown in FIG.
Shown in the figure. FIG. 2B shows shutter running characteristics when exposure unevenness is corrected by controlling the average running speed of the leading blade 1 instead of the method of controlling the running of the shutter trailing blade 2 shown in FIG. , FIG. 2 (C) shows the exposure amount in the screen corresponding to FIG. 2 (B). In FIG. 2, the shutter leading blade 1C locus 1C ₂ 'when increasing the speed to draw a, the exposure amount b ₁ of the first embodiment' exposure at the beginning A as similarly to the exposure amount b ₂ ' In contrast, the absolute value of the deviation of the maximum exposure amount and the deviation of the minimum exposure amount are equal to each other. Furthermore, the shutter leading blade 2 is corrected so as to draw a locus 1C ₂ ′, and the timing at which the trailing shutter blade 2 starts traveling is advanced at time t ₂₂ , so that the exposure amount of the entire screen is changed as in the first embodiment. The vehicle travels along the trajectory of the dotted line 2C ₂ so as not to increase too much and the shutter speed does not become too slower than the expected value or the set value. In this way, by controlling the traveling characteristics of the leading and trailing shutter blades, the exposure amount in FIG. 2 (C) changes from the solid line b to the broken line b ₂ , and the same effect as in the first embodiment is obtained. To be

Next, a specific method for controlling the shutter device will be described. A specific shutter device of the first embodiment will be described with reference to FIGS. 3 to 6. FIG. 3 is a perspective view of the shutter device, FIGS. 4 and 5 are enlarged perspective views of a part of the shutter device, and FIG. 6 is a control block diagram of the shutter device. In FIG. 3, the leading shutter blade 1 is rotatably attached to the pins 3a and 3b provided at the tips of the parallel arms 5 and 6, and the trailing shutter blade 2 is provided at the tips of the parallel arms 7 and 8. It is rotatably attached to each of the pins 4a and 4b. The other ends of the parallel arms 5 and 6 are rotatably supported by shafts 10 and 11 which are planted in the shutter substrate 9, respectively, to form a parallel link. Similarly, parallel arms 7 and 8
The other end of each of the shafts 12 is planted on the shutter substrate 9.
And 13 are rotatably supported to form parallel links.

The parallel arm 5 has an L-shape, and a biasing spring 14 is provided on the shaft 10 so that the parallel arm 5 rotates right about the shaft 10. A leading blade locking key 16 that locks the right arm of the parallel arm 5 is rotatably supported by the shutter substrate 9, and the tip of the locking key 16 contacts the L-shaped end of the parallel arm 5 to rotate the right arm. It is prohibited. The parallel arm 8 is L-shaped, and a biasing spring 15 is provided on the shaft 13 so that the parallel arm 8 rotates right about the shaft 13. A rear blade locking key 17 that locks the right arm of the parallel arm 8 is rotatably supported by the shutter base plate 9, and the hook of the locking key 17 engages with the L-shaped tip of the parallel arm 8 to rotate the right arm. Is prohibited. When the leading blade locking key 16 and the trailing blade locking key 17 are disengaged from the parallel arms 5 and 8, the biasing springs 14 and 15 are
The shutter leading blade 1 and the shutter trailing blade 2 are moved substantially in parallel with each other and cross the aperture 9a to expose the film. That is, the slit formed by the slit edge 1a of the front shutter blade 1 and the slit edge 2a of the rear shutter blade 2 crosses the aperture 9a opened in the shutter substrate 9 to slit expose the film screen.

An accelerating lever 18 is rotatably attached to the upper portion of the shaft 13, and is urged in a clockwise direction by an accelerating spring 19. A pin 20 is planted at one end 18a of the acceleration lever 18, and the pin 20 is attached to the rear blade unit (parallel link 7,
8 and the shutter rear blade 2 and the biasing spring 15), the biasing force of the acceleration spring 19 is transmitted to the parallel arm 8. Also,
The other end 18b of the acceleration lever 18 is hooked by the acceleration lever locking key 21, and the acceleration lever 18 is locked against the biasing force of the biasing spring 19. The locking key 21 is rotatably supported by a shaft 22 that is planted in a part 9b of the shutter substrate 9, and is biased counterclockwise by a biasing spring 26 so that the locking key 21 has one end 21a. The amateur 23 is provided.

A magnet composed of a yoke 24 and a coil 25 for attracting and fixing the armature 23 is provided on a part 9b of the shutter substrate 9 which is integrally provided with the shutter substrate 9. This magnet locks the locking key 21 against the biasing spring 26 that biases the locking key 21 in the counterclockwise direction.

FIG. 4 shows a state around the parallel arm 5 of FIG. 3, and a trigger switch 36 for operating the trailing blade control circuit 44 is in contact with one end of the locking key 16, and this trigger switch 36 is configured so that the locking key 16 is turned off in relation to the operation of unlocking the arm 5. Also, when the parallel arm 5 starts to rotate clockwise, the synchro switch 31 for causing the speedlight device to emit light is turned on.

FIG. 5 shows a state around the parallel arm 8 in FIG. 3, and the start switch 32 for detecting the start of traveling of the shutter rear blades 2 is an operation in which the lock key 17 releases the lock on the parallel arm 8. Is configured to be off in relation to.

In FIG. 6, the speedlight 38 and the camera 37 have terminals a-
It is shown that they are electrically connected by a ', b-b', c-c '. In the speedlight 38, there is a speedlight use information signal indicating that the speedlight is ready to emit light (for example, when the power switch of the speedlight is turned on or when the main capacitor is charged to a required amount). A speedlight signal source 40 for outputting and a light emission control circuit 41 which is operable in association with the use information signal and controls light emission of a flash tube are installed. In addition, in the camera, a leading blade release circuit 48 and a leading blade release mechanism 49 which are operated by a signal from the release switch 35.
And an arithmetic circuit 43 for performing an exposure calculation based on the photometric value of the photometric circuit to obtain an appropriate shutter speed and outputting the signal or a shutter speed signal set by the shutter dial, and the speedlight use information signal. From the determination circuit 42 that determines whether or not the shutter speed is for the slit synchronized photography from the arithmetic circuit 43, the shutter rear blade control circuit 44 that controls the shutter rear blade, and the shutter rear blade control circuit 44. The trailing blade release circuit 46 and the trailing blade release mechanism 47 which are operated by the signal of the above, and the energizing time to the magnets 24 and 25 which is activated only during the slit synchronization photographing, and the operation circuit 4
A travel control circuit 45 that changes according to the shutter speed signal of 3 is installed. The discriminating circuit 42 receives the use information signal from the speedlight signal source 40 and the slit synchronizing shutter speed signal (for example, a shutter speed of 1/800 seconds or more) from the arithmetic circuit 43 when the slit synchronizing signal is input. A shooting mode signal is output and a command is sent to the trailing blade control circuit 44 and the traveling control circuit 45. The trailing blade control circuit 44 is provided with two serial timer circuits that operate in association with the trigger switch 36, and the sum of the time counts of the two timer circuits follows the shutter speed information signal of the arithmetic circuit 43. . However, one of the timer circuits shortens the time measured when the slit synchronization photographing mode signal is input from the determination circuit 42, and the trailing blade control circuit 44 outputs the shutter speed information signal according to the shutter speed information signal. The later the shutter, the signal for advancing the traveling start time of the rear blade 2 is output. Further, the traveling control circuit 45 controls the energization time to the magnets 24 and 25 to be shorter as the shutter speed becomes higher when the slit synchronization photographing mode signal is input. Therefore,
At the time of slit sync photography, the shutter blades are controlled by the sum of the operating times of the two timer circuits and the energization time of the magnets by the traveling control circuit 45 so that an appropriate exposure time is obtained.
The traveling speed varying means of the present invention is the acceleration lever 18 of the embodiment,
It corresponds to the acceleration spring 19, the acceleration lever locking key 21, the biasing spring 26, the magnets 24 and 25, and the traveling control circuit 45.

Next, the operation will be described with reference to FIGS. First, the case of performing normal shooting will be described. Release button
When the switch 33 is pushed halfway, the switch 34 is turned on, and the electric circuit in the camera is turned on. In addition, when the release button 33 is pressed down, the release switch continues to the switch 34.
35 is turned on, and in response to the switch 35 being turned on, the leading blade release circuit 48 and the mechanism 49 are operated. However, even if the switch 35 is turned on, the traveling control circuit 45 does not operate because the inactivation signal is input from the determination circuit 42 because it is not the slit synchronization photography. With respect to the leading blade release mechanism 49, the reset lever 27 is rotated clockwise about the shaft 28 by the mechanism shown in FIG. A pin implanted at one end of this reset lever 27
29 is separated from the acceleration lever locking key 21. At that time, as described above, since the traveling control circuit 45 is inoperative, the magnets 24 and 25 do not function, and the acceleration lever locking key 2
The amateur 23 provided in 1 is not adsorbed. Therefore, the locking key 21 rotates counterclockwise about the shaft 22 to release the locking of the acceleration lever 18, and the acceleration lever 18 can rotate right.
The biasing force of the biasing spring 19 in the clockwise direction is applied to the parallel arms 8 and 7. However, at this time, since the parallel arm 8 is locked by the trailing blade locking key 17, the shutter trailing blade 2 does not run.

In connection with the shutter release (release switch 35 ON) operation, the above-described operation is performed and the shutter leading blade 1 is made to travel. Leading blade release mechanism 49
Releases the locking of the leading blade locking key 16 to the parallel arm 5. The parallel arm 5 is urged in the clockwise direction by the urging force of the urging spring 14 to drive the shutter leading blade 1. The leading blade 1 starts opening the aperture 9a. At this time, the key 16 turns off the trigger switch 36 shown in FIG. Then, the shutter rear blade control circuit shown in FIG.
44 is a built-in timer circuit that starts timekeeping. This timer circuit is based on the shutter speed set by the arithmetic circuit 43, and the shutter rear blade control circuit 44 is a rear blade release circuit.
46, a signal is sent to the mechanism 47, and the trailing blade locking mechanism 17 releases the trailing blade locking key 17 from the locking of the parallel arm 8. Therefore, the parallel arm 8 moves together with the parallel arm 7 by the sum of the urging forces of the urging springs 15 and 19.
Turn right and start closing the aperture 9a. The bias spring
The sum of the urging forces of 15 and 19 is equal to the urging force of the urging spring 14 so that the slit edge 1a of the leading shutter blade 1 and the slit edge 2a of the trailing shutter blade 2 cross the aperture 9a at substantially the same time. It has been set against.
As described above, the exposure of the film is completed at the shutter speed set by the arithmetic circuit 43.

Next, when the shutter charge is performed manually or automatically, the parallel arms 5 to 8 turn counterclockwise in FIG. 3, and the parallel arms 5 and 8 therein are locked by the locking keys 16 and 17, respectively, and the shutter leading blades are locked. 1 and the shutter rear blade 2 are reset, and the shutter front blade 1 covers the aperture 9a. Further, the acceleration lever 18 is a pin that abuts the parallel arm 8.
While rotating counterclockwise through 20, the reset lever 27 is also rotated counterclockwise and the acceleration lever locking key 21 is rotated right through the pin 29, and the acceleration lever 18 is locked by the acceleration lever locking key 21. By the counterclockwise rotation of the reset lever 27, the armature 23 provided on the acceleration lever locking key 21 is pressed against the magnets 24, 25.

Next, the shutter operation when performing slit sync photography will be described. First, the power of the speedlight device 38 is turned on, and when the release button 33 is pushed halfway in FIG. 3, the power switch 34 is turned on and the power is turned on as described above. Then, in the block diagram shown in FIG. 6, the speedlight use information signal from the speedlight signal source 40 and the shutter speed signal (for example, in the range of 1/4000 to 1/800 seconds) that causes slit synchronization from the arithmetic circuit 43. When the signal is input to the discrimination circuit 42, the discrimination circuit 42 determines that it is the slit synchronized photographing, and outputs the slit synchronized photographing mode signal. At this time, further pressing down the release button 33 turns on the release switch 35. Since the slit synchronization photographing mode signal is input to the traveling control circuit 45 from the determination circuit 42, when the release switch 35 is turned on, the traveling control circuit 45 operates and the coil 25 of the magnet is energized. Therefore, the amateur 23 is attracted to the yoke 24. Therefore, even if the reset lever 27 is associated with the leading blade release mechanism 49 and rotates clockwise to retract, the acceleration lever locking key 21 does not rotate counterclockwise and locks the acceleration lever 18 against the biasing force of the biasing spring 19. To do.

In connection with the shutter release (the release switch 35 is turned on) operation, the above-described operation is performed, and the shutter leading blade 1 runs. The leading blade release mechanism
49 is a key for locking the leading blade 16 when the switch 35 is turned on.
The parallel arm 5 is unlocked, and the shutter leading blade 1 is made to travel. At this time, as shown in FIG. 4, the locking key 16 turns off the trigger switch 36, and the parallel arm 5 turns on the synchro switch 31 to activate the flashlight emission control circuit 41 to cause the flash tube to emit light. When the trigger switch 36 is turned off, the two timer circuits of the shutter trailing blade control circuit 44 shown in FIG. 6 start to operate sequentially, and the shutter trailing blade control circuit 44 sets the predetermined time (setting (A shutter speed), a slightly shorter time is measured, and as shown in the first drawing, a command signal for the traveling start timing of the trailing blade 2 is sent to the trailing blade release circuit 46 earlier, and the trailing blade release mechanism 47 releases the shutter at time t ₂ . Release the rear blade locking key 17 to release the shutter rear blade 2
Run. This means that the exposure time becomes substantially longer when the average traveling speed of the shutter rear blades 2 is changed, as indicated by the alternate long and short dash line 2C ′ and the broken line 2C ″ shown in FIG. 1B. When the locking key 17 is actuated, the start switch 32 is turned off and the timer circuit of the traveling control circuit 45 starts timing as shown in Fig. 5. Then, the shutter rear blade 2 is biased by the biasing spring 15. Slit edge 2a is aperture 9a when the vehicle starts running with only the biasing force.
At a certain point before starting to cover the vehicle, the timer circuit of the traveling control circuit 45 finishes counting the predetermined time (correction time) and cuts off the energization of the coil 25 of the magnet of the traveling speed varying means, and supplies power to the coil 25. When the lock is released, the locking key 21 is rotated counterclockwise by the urging force of the urging spring 26 to release the locking of the acceleration lever 18. Then, the accelerating lever 18 turns right by the urging force of the urging spring 19 and catches up with the parallel arm 8 which was running earlier, and thereafter the shutter rear blade 2 is turned right by the urging springs 15 and 19. Become. Therefore, the shutter rear blade 2
Is driven only by the urging spring 15 at the beginning of traveling, and is then driven by the sum of the urging forces of the urging springs 15 and 19 after a lapse of the correction time, and the chain line 2C shown in FIG. It is possible to realize the shutter running characteristics as shown by the dashed line 2C '. The correction time is appropriately determined by the value of the set shutter speed input from the arithmetic circuit 43 by the discriminating circuit 42, and is indicated by a dashed line in FIG. 2C 'and broken line 2C "have driving characteristics.

Even with the same slit sync photography, at high shutter speeds (about 1/4000), exposure unevenness is small without correcting the shutter running characteristics, so the energization time to the coil 25 is shortened and the shutter trailing blades 2 accelerate immediately after running. Spring
19 is used, and the average traveling speed of the rear blades 2 of the shutter is not reduced so much. However, if the shutter running characteristics are not corrected in the low-speed shutter (about 1/1000), the exposure unevenness is large in slit synchronization photography, so the energization time to the coil 25 is lengthened, and after the trailing shutter blade 2 starts running, there is a delay. By activating the acceleration spring 19, the average traveling speed of the rear blades 2 of the shutter can be further reduced and the adverse effect of uneven exposure can be eliminated. However, even in that case, the slit edge 2a of the rear blade 2 of the shutter has the aperture 9a.
It is preferable to activate the acceleration spring 19 before the cover starts to be covered. This is because if the pin 20 collides with the arm 8 when the acceleration lever 18 catches up with the arm 8 while traveling through the aperture 9a, a clear exposure unevenness is likely to occur due to the impact and a sudden change in traveling characteristics.

Therefore, by controlling the running characteristics of the rear blades of the shutter in this way, slit synchronization photography is possible and the adverse effect of exposure unevenness at that time is eliminated. As described above, in the present embodiment, a traveling control device having a simple structure and a reliable operation is obtained by using an electric attraction type magnet device which is easily available and inexpensive, and by controlling the energization time.

Next, a specific control method of the shutter blades of FIG. 2 which is the second embodiment will be described based on FIGS. 7 to 9. When performing normal speedlight photography other than slit sync photography, the operation is the same as that of the shutter device of FIG. Now, slit sync photography will be described. In FIG.
A coil 29a which rotates integrally with the arm 5 is installed above the axis 10 of the parallel arm 5. Further, at the center of the coil 29a, there is a permanent magnet 30 integrally fixed to the shaft 10 with a slight clearance from the coil. Further, the yoke 29b is integrally fixed to the magnet 30 with a gap so as not to come into contact with the coil on the outer periphery of the coil 29a, thereby improving the magnetic efficiency. The direction of the poles of the permanent magnets and the polarity of the magnetic field when the coil is energized are selected and arranged in the direction in which the torque is generated in the right-handed direction almost throughout the traveling of the leading blade 1. Of course, the arrangement may be such that the torque is generated only when the leading blade is activated. When the coil 29a is energized, the shutter leading blades that rotate integrally with the coil 29a are accelerated in the clockwise direction. The traveling speed varying means of the present invention corresponds to the coil 29a, the permanent magnet 30, the yoke 29b, and the traveling control circuit 50 of the embodiment.

The operation of the shutter device shown in FIG. 7 will be described. However, in this embodiment, the urging forces of the urging springs 14 and 15 are set so that there is no exposure unevenness. Now, in the case of slit synchronization photography, when the release button 33 is pushed in, the power switch 34 is turned on and the electric circuit of the camera is turned on. When the release button 33 is further depressed, the release switch 35 is turned on following the switch 34, and the leading blade release mechanism (not shown) operates. At this time, in FIG.
Since the shutter speed signal capable of slit synchronization photography from the arithmetic circuit 43 and the speedlight use information signal from the speedlight signal source 40 are input to the determination circuit 42,
The coil 29a is energized by the operation of the traveling control circuit 50.
Then, as the leading blade release circuit 48 is operated, the leading blade release mechanism 49 is operated and the leading blade locking key 16 is moved to the parallel arm 5.
Unlock the. Then, the shutter leading blades 1 move the torque generated by the coil 29a and the permanent magnet 30 and the biasing spring 14.
Since the vehicle can be driven with the sum of the urging forces of and, the vehicle will start traveling at a greater acceleration than usual. Therefore, as shown in FIG. 2 (B), the shutter leading blade 1 travels along a locus of 1C '.

Interlocking with the operation of the leading blade locking key 16, the trigger switch 36 and the start switch 39 shown in FIG. 8 are turned off and the synchro switch 31 is turned on. This synchro switch
When 31 is turned on, the light emission control circuit 41 operates and the flash tube starts emitting light. Further, by turning off the trigger switch 36 and the start switch 39, the timer circuit of the trailing blade control circuit 44 operates and the timer circuit of the traveling control circuit 50 operates. Due to the timing of the timer circuit of the travel control circuit 50 that is operated in conjunction with the start of travel of the shutter leading blade 1, the coil 29a is de-energized before the slit edge 1a of the shutter leading blade 1 starts opening the aperture 9a. Therefore, the shutter leading blade 1 travels only by the urging force of the urging spring 14 from when the coil 29a is de-energized. Since the unevenness of exposure on the screen varies depending on the shutter speed, the energization time of the coil 29a should be controlled by the shutter speed information signal from the arithmetic circuit 43, that is, the length of the shutter speed, in order to reduce this uneven exposure. Good.

At this time, since the slit synchronization shooting mode signal was input from the determination circuit 42 to the rear blade control circuit 44, the circuit
As shown in FIG. 2B, the timer circuit 44 outputs a control signal to the trailing blade release circuit 46 and the release mechanism 47 so that the shutter trailing blade 2 starts running at a slightly earlier time t _2. To do. The rear blade control circuit 44 is composed of two timer circuits as in the first embodiment, and the sum of the time counts of the two timer circuits corresponds to the shutter speed as it is when the slit synchro photographing is not performed. However, at the time of slit synchronization photography, one timer circuit operates so as to slightly advance the traveling start time of the shutter rear blade 2 as described above, and the other timer circuit measures a certain time based on the shutter speed signal from the arithmetic circuit 43. Then, the rear shutter blades 2 are controlled by the two timer circuits so as to draw the locus of 2C in FIG. 2 (B). In this way, the shutter rear blade 2 is also controlled because the total exposure amount in the screen increases and the shutter speed tends to be long because the traveling characteristic correction control is performed on the shutter front blade 1 as described above. This is because the running start timing of the trailing blades 2 must be advanced in order to correct this to a value before correction of the running characteristics.

Therefore, even with such a shutter leading blade control system,
Since the exposure amount on the film surface can be controlled as indicated by b in FIG. 2 (C), the same effect as the above-mentioned control of the shutter rear blade can be obtained.

The present invention is not limited to the embodiments, and for example,
Instead of the discrimination circuit 42, a slit synchro photographing mode signal may be generated by an external operation member, and even if slit synchro photographing is not performed, it may be configured to cause uneven exposure on the screen according to the intention of photographing, and if configured in this way, Exposure unevenness can be intentionally generated even when shooting without a speedlight, so the exposure balance between the main subject and the background even in situations where a part of the screen is bright such as landscapes and group photos You can get a good picture. Further, although the shutter blade is a single thin plate in the embodiment, it may be composed of a plurality of divided blades, or a shutter of a system in which a flexible curtain is wound around a cylindrical drum may be used. Further, in the device of the system in which the shutter leading blade of the second embodiment is controlled by the coil and the permanent magnet, instead of the method of changing the energization time to this coil, for example,
A method of changing the current while keeping the energization time constant may be used. Further, in the device using the coil and the permanent magnet, the driving force for moving the shutter blades can be freely controlled, so that the acceleration can be continued by the electromagnetic force even while traveling in the screen, and the acceleration force can be controlled. It is also possible to correct uneven exposure.

As described above, according to the present invention, the traveling speed varying means for changing the average traveling speed of one or both of the shutter front member and the shutter rear member is provided in association with the control signal of the control means. Therefore, the photographer can intentionally control the unevenness of the exposure of the screen according to the photographing situation, and the photographing suitable for the photographing intention can be performed.

It should be noted that, as in the embodiment of the present invention, when the light emission preparation signal indicating the light emission preparation operation of the electronic flash device and the high-speed shutter speed signal of the specific value or more are input to the control means from the arithmetic means outputting the shutter speed signal, When performing slit synchro photography, the control means (discrimination circuit) outputs a control signal (slit synchro photography mode signal), and the traveling speed varying means appropriately changes the traveling characteristics of the shutter blades according to the control signal. Therefore, the exposure unevenness on the screen can be reduced, and the speedlight shooting can be performed over a wide range of shutter speeds, so that the shooting range can be expanded.

[Brief description of drawings]

FIG. 1 (A) is a light emission characteristic diagram of the electronic flash device, FIG. 1 (B) is a running characteristic diagram of the shutter device of the first embodiment according to the present invention, and FIG. 1 (C) is a film surface by the shutter device. 2B is a running characteristic diagram of the shutter device according to the second embodiment of the present invention, and FIG. 2C is an exposure characteristic diagram of the film surface by the shutter device. FIG. 3 is a perspective view of the shutter device of the first embodiment, FIGS. 4 and 5 are partially enlarged views of the shutter device, and FIG. 6 is a camera incorporating the electronic flash device and the shutter device. Shows a block diagram of
FIG. 7 shows a perspective view of the shutter device of the second embodiment,
FIG. 8 shows a partially enlarged view of the shutter device, and FIG.
The figure shows a block diagram of a camera incorporating the electronic flash device and the shutter device. 10 (A) and 11 (A) are emission characteristic diagrams of the electronic flash device, FIGS. 10 (B) and 11 (B) are running characteristic diagrams of the conventional shutter device, and FIG. 10 (C). ) And FIG. 11 (C) are exposure characteristic diagrams of the film surface by the shutter device. (Explanation of symbols of main parts) 1 ... Shutter front blade 2 ... Shutter rear blade 16 ... Front blade locking key 17 ... Rear blade locking key 18 ... Accelerating lever 19 ... Accelerating spring 21 ... Accelerating Lever locking key 24; 29b ...... Yoke 25; 29a ...... Coil 30 ...... Permanent magnet 31 ...... Synchronizing switch 34 ...... Power switch 35 ...... Release switch 42 ...... Discrimination circuit 44 ...... Rear blade control circuit 45; 50 …… Running control circuit

Claims (4)

[Claims] 1. A shutter front member having a first slit forming portion and a shutter rear member having a second slit forming portion can be independently operated, and the first slit forming portion and the shutter rear member can be operated independently. In a shutter device that sequentially exposes a film surface with a slit formed by a second slit forming portion, an average traveling speed when the first slit forming portion travels on the film surface and the film surface Among the average traveling speeds when the slit forming section 2 travels, at least one of the average traveling speeds is changed, and a traveling speed varying means and a control means for outputting a control signal for operating the traveling speed varying means are provided. A shutter device capable of correcting traveling characteristics, which is characterized in that 2. The shutter device is capable of interlocking with an electronic flash device, and the control means outputs a preparation signal indicating a light emission preparation operation of the electronic flash device and a shutter speed signal from a means for a predetermined shutter time or more. The shutter device capable of correcting the traveling characteristics according to claim 1, wherein the control signal is output when a high-speed signal indicating the shutter speed is input. 3. The control means, when a preparation signal indicating a light emission preparation operation of the electronic flash device and a high speed signal indicating a shutter time of a predetermined shutter time or more are input from a means for outputting a shutter speed signal, 2. The traveling characteristic according to claim 1, wherein the control signal is changed according to a high-speed signal, and the traveling speed varying means changes the traveling speed of the shutter member according to the control signal. Correctable shutter device. 4. The shutter according to claim 4, wherein the traveling speed varying means lengthens the exposure time to the film surface as the distance to the exposure end area becomes closer, when performing slit synchronization photography at a high shutter speed longer than the predetermined shutter time. The shutter device capable of correcting traveling characteristics according to claim 3, wherein the shutter device controls members.